The product name in your db looks as though you may have rules on how to construct it. You don't have 'laptop', 'model', 'no', parens or dashes in it. Are all the names constructed in the same way? Perhaps filter them out first.

Is the number at the end of the record unique? Do you have rules for constructing those? Perhaps concentrate on that.

How many merchants are there? Are their naming conventions consistant? If they ordered the same m/c two days running would it be the same?

I'd consider a separate table with the (filtered) alternatives pointing to your main db and flag up non matches. It would still mean there would be manual work to do but it would tail off.

As suaveant notes normalising data is a pain.

Good luck!